Inter-rater reliability of treatment fidelity and therapeutic alliance measures for psychological therapies for anxiety in young people with autism spectrum disorders

Objectives: This article presents work undertaken to establish inter-rater reliability for a measure of treatment fidelity and a measure of therapeutic alliance for therapies for anxiety for young people with autism spectrum disorders. The discussion and decision-making processes behind achieving consensus of raters are rarely published. Margolin et al. (1998) have highlighted this issue and called for researchers to communicate the details of their observational and rating procedures. This article is a response to their call for greater transparency so that these methods are readily accessible for comparison with other studies. Methods: Participants were young people with autism spectrum disorders receiving treatment for anxiety, clinical staff treating these young people and the independent raters assessing the treatment sessions. We report: (i) the processes involved in establishing inter-rater reliability for two instruments, (ii) the results obtained with a sample of young people with autism spectrum disorders using these instruments. Results and conclusions: Results demonstrate that it was possible to attain satisfactory inter-rater reliability with each of these two instruments with a client group with autism spectrum disorders, even though the instruments were originally designed for typically-developing populations.